Process for clarifying and improving the color of petroleum oils



y M. L. CHAPPELL'AND M. M. MooRE. 1

PROCESS FOR CLARIFYING AND IMPROVING THE COLOR 0F P ERO LEUM OILS.APPLlcAUoN nLb'rEB. 1a, 14929.

UNITED STATES MARVIN L. CHAPPELL AND MERLE M.

ASSIGNORS TO STANDARD OIL COMPANY OF CALIFORNIA,

PATENT OFFICE.

MOORE, or EL sEoUNDo, CALIFORNIA,

or s AN FRAN- `ISCO, CALIFORNIA, A CORPORATION OIE'- CALIFORNIA.

PROCESS FOR CLARIFYING AND IMPROVING THE COLOR F PETROLEUM OILS.

Specification of Letters Patent.

Patented Jan. 24 1922.

Application led February 18, 1920. Serial No. 359,755.

' To all whom t may concern:

Be it known that we, MARVIN L. CHAP- PELL and MERLE M. MooRE, citizensof the United States, residing at El Segundo, in the county of LosAngeles and State of California, have invented anew and usefulProcessfor Clarifying and Improving the Color of Petroleum Oils, ofwhich the followin "is a specification.

rIhisfinvention relates to the art of clarifyingand iInp-roving thecolor of petroleum oils by the use df clarifying and decolorizin agents.While not necearily limited t ereto, it more specifically refers to theart of clarifyin and improving the color of lubricating o1 s.

One object of the invention is to provide a method orv process whereby asubstantially uniform clarified oil of the desired color may be producedwith a minimum consump- .tion of the clariffying decolorizing agent;

another object is to' provide such a process which may be performed witha minimum consumption `of time.

An object `of the invention is to provide a method whereby` hydrocarbonoil may be mixed with a clarifying and decolorizing agent and quicklyheated to a temperature of. 250D F, or higher, thoroughly commingled andcooled before any substantially oxidizing action can take place.

An object of the invention is to.provi-de a method whereby a more finelycomminuted decolorizin and clarifying agent may be used to clarifgy anddecolorize a petroleum `hydrocarbon oil than has heretofore been used.

' dized products.`

An object of the invention is to provide a process, for the purposespecified, whereby the oil to be treated and the clarifying anddecolorizing agent may be thoroughly intermingled, in any suitablemanner, and not depend upon percolation of the o11 through ,the agent.

An objectof the invention is to provide a method 4or process whereby`the treated oil maybe quickly cooled and" filteredl with'- out loss invcolor The extraction of coloring matter from petroleum oils-is'.generally understood to vbe an adsorbing process, dependent upon time ofcontact, temperature and. surface lexposed. For example, for a givenquantity pass through a 15 to -3(1) mesh sieve.

for the formation o'f Aoxi# and weight the finer the comminutlon of thedecolorizing agent, the more surface thereoffwill be exposed to the oiland the more coloring matter will be condensed or adsorbed upon thesurface of the decolorizing agent. We have found that` a decolorizingagent, ground so that approximately 97 wlll pass through a 200 meshsieve or screen, gives the more satisfactory results for our process ormethod.

Heretofor by usual methods it has been customary to clarify. and improvethe color of hydrocarbon oils and particularly lubri- -cating oils bypercolating such oil through long pipes or othen 'forms of containersfilled with a decolorizing 'and clarifying agent, such ldecolorizingand' clarifying agent comminuted` or finely divided so it will passthrough a No. d0 standard mesh sieve but will be retained on a No.` meshstandard sieve; also when fullers earth 'is used for the more viscousoils, the same With our process as hereinafter described and explainedwe require only approximatelyv 2 hours for the entire ltreatment of' theoil for the purpose `of decolorization and clarification and at the sametime lretain the oil with a greater viscosity than where the usualmethods or processes 4are used, and also are enabled to perform theclarification and' decolorization lwithv a minimum consumptio'n ofdecolorizing and clarifying By ourv pfocess also we obtain a superiorvproduct and substantially free from" oxif dized products. l

By our process inits preferred form, we mix the clarifyingfagentdirectly with the oi1,'a ndd'o not rdepend upon mere percolaltion of theoil through such agent.

In the preferred embodiment of our invention our method or process inclarifying or improving theV colorfof hydrocarbon oil, consists eitherin batch treatments or by continuous methods whereby hydrocarbonpetroleum or lubricating oil is quickly heated to 250 F. or higher bysuitable heating devices, while such 'oil is commingled with aclarifying and decolorizing agent 1n a nely comminuted or pulverizedcondition and in such quantities as is necessary to obtain the desiredcolor and grade; continuing the commingling or agitating of suchhydrocarbon oil and decolorizing agent for such a period of time and atsuch a temperature as is necessary to obtain the desired extraction ofcolor from such oil; then immediately partially cooling said oil andseparating therefrom the decolorizing agent and adsorbed matter, bysuitable means; and finally cooling said oil to the desired temperature.

More specifically our invention provides a process whereby hydrocarbonoil may be heated (substantially 250o F. or above) by rapid circulationthrough heated piper coils or tubes or in any suitable vesselor'chamber, without any part of said oil Lbeing heated beyond `thedesired temperature; thoroughly commingling the heated oil anddecolorizing and clarifying agent; quickly partially cooling the same.below oxidizing temperature so as to minimize the oxidation; separatingthe adsorbed decolorizing and clarifying agent and coloring-matter fromthe oil; and then cooling the oil to the desired temperature.

The preferred embodiment of our invention will be more readilyunderstood by ref-' nerence to the accompanying drawings, illustrating aform of apparatus by which, the same may be performed. The drawing is adiagrammatical formvof an apparatus by which such preferred embodimentof our invention. may be performed.

In the drawings 2 represents a storage tank for the oil to be treated.This tank2 is connected -by a pipe `3 with a treating tank 4. The tank 4may be entirely open at its topor may be closed by av dome 5 asindicated in the drawings and yprovided i with a vapor outlet 6. Thetreating tank 4 is connected by means of a pipe 7 to a pump.

8 which discharges through a pipe 9 connected through a valve 10.to aheater 11 and through a valve 12 to a cooler 13. The heater 11 may be ofany suitable form of construction but. we prefer to'usea Braun heaterwhich is a ,heater composed of small pipes enclosed in ashell so thatthe heating medium fills the shell and surrounds the pipes through whichthe oil is conducted, thus affording a quick means of raising thetemperaturey of the oil as it passes quickly to a desired temperaturethrough the pipes or tubes of the heater. This heater 11 is connectedbymeans of a pipe 14 to the treating tank l4; As shown in the drawingsthe heater 411 is also connected by a pipe 15 to the pump 8. 16represents a valve in the pipe or vline 15 and 17 represents .a valve inthe pipe or line 7. 18 represents a storage and feeder bin or hopper'inwhich the iinely comminuted clarifying or decolorizing agent isprovided. From this bin 18 such agent may be introduced into thetreating tank 4 in the desired quantities, such 'quantities beingregulated by means of a suitable slide or valve 19. 13 represents acooler which is connected to receiver 21 by a suitable pipe 22. Thereceiver 21 may be connected to a pump 23 by pipe 24. The epump 23discharges through a pipe 25 which in turn is connected to a filterpress, device or chamber 26 of any ordinary or preferred con-lstruction. 27 represents a receiving pan to hold the spent clarifyingand decolorizing agent. 28 represents a conveyor to convey the spentclarifying and decolorizing agent to storage or for recovery.

Th ltering device or press 26 is connected to a cooler 29 by a suitablepipe 3() and in turn the cooler 29l is suitably connected to a storagevessel 31 as by a pipe 32. 33 indicates a pipe which leads from thestorage' vessel 31 to any other suitable place or means of Storage. Whenthe apparatus is in ther form shown in the drawing the preferred,embodiment of our processv is performed as follows: L v

The treating tank 4 is first filleid with the predetermined amount ofhydrocarbon oil to be treated, such oil being drawn through the pipe 3from the storage tank 2. De-

colorizing and clarifying agent in the I equired amount is then added bysuitable operation of the valve 19. This decolorizing agent isthoroughly commingled'with the oil by any suitable means, such forinstance, as circulation by means of the pump 8 through 'the heater 11and back into the tank 4. This circulation is continued until thecommingled decolorizing agent and oil is raised to a temperature ofapproximately 25()o F., depending upon the oil to be treated. After thecommingled oil and agent have thus been raised to the desired temper--temperature for the desired length of timel without subjecting anyportion of the oil to a greater temperature than desired, thusminimizing the oxidation which would be promoted by toohigh atemperature and eliminating the danger of any portion of the oilapproachingv decomposing. temperature.-

After thus being subjected to the critical temperature for the desiredlength of time the commingled oil and agent are immediately passedthrough a suitable cooler, such as the cooler 13 indicated in thedrawings. In this cooler the temperature of the com.- mingled oil-andagent is reduced below the temperature of rapid oxidation and dischargedinto a sultable receiver 21 from which they are drawn by the pump 23 anddischarged-through the filtering press or .apparatus 26, where theclarifying agent with the adsorbed coloring matter is separated from theoil and discharged and the clarified and decolorizedv oil is dischargedinto the cooler 29 from which cooler suh oil may be passed to anysuitable storage vessel such as the storage vessel 31.

The passage of the commingledoil andagentthrough the heater 11 graduallybut very quickly heats the commingled oil and agent to the desiredtemperature without heating any vmaterial quantity of the oil beyondthis temperature'.

The passage of the treated hydrocarbon oil through the cooler 13 rapidlycools said oil to a .temperature at which no material" oxidation ormaterial lowering in the color of the oil will occur upon standing. Thistemperature is regulated to conform to the filtering rate of the oil. Weprefer to maintain a .slightly higher temperature during the filtrationof oils which are of'a heavy viscosity.

While we prefer to use a filter press as the means of separating theclarifying and decolorizing agent from the oil, our process is notnecessarily limited theretoas we may use any suitable filtering means,centrifugal machine or other mechanical device by means of which the oilis obtained substantially free from vthe spent clarifying anddecolorizing agent.n p

As a clarifying and decolorizing agent we may use animal char, bone ash,fullers earth, certain vclays which have been treated with acid, such asthe clays froml the well-known Death Valley, California, deposits, withadsorbent qualities. or any other or preferred lmaterial suitabletherefor, and which will clarify and improve the color of the oil.

In utilizing our process for clarifying and decolorizin certainlubricating oils de-v rived from Ca ifornia crude oils, wehave foundthat by quickly. raising the temperature of the commingledvoil anddecolorizing agent to approximately 300 F.' and maintaining same at suchtemperature for approximately 5 minutes and then quicklycooling the sameto approximately 150, we secure the best results. -It lis obvious,

therefore, that our process is not limited specifically to a particulartemperature, the range of temperature .to which the commingled oil andagent shall be subjected being from substantially '250 F. to the heat ortemperature at which the peak of the reac- 'ton takes place. `Bestresults are secured by the higher temperatures so long asV the-temperature of the commingled oil and agent is retained below thetemperature of the peak of reaction.

We claim:

1. The process of clarifying and improving the color of a hydrocarbonpetroleum oil which consists in commingling with the oil a clarifyingand decolorizing agent comminuted so that substantially 97% of suchagent vwill pass through a200 mesh sieve orvscreen, quickly raising'thecommingled oil and agent'to a temperature not substantially less-than250o F. and below the peak of the decolorizing reaction, maintainingsuch temperature until the reaction `is effected, immediately coolingsuch oil and lagent below the temperature of rapid oxidation, andseparating the oil and agent with itsladsorbed coloring matter.

2.- The process of clarifying and improving the color of a hydrocarbonpetroleum oil which consists in quickly raising such oil commingled witha finely divided clarifying and decolorizing agent to a temperature notsubstantially less Jthan 250o F. and below the decolorizing point ofchemical reaction, maintaining such heat'during the period of suchreaction, immediately partially cooling the intermingled oil and agentbelow the temperature of rapid oxidation7 ico and separating the oil andagent" with its adsorbed coloring matter. Y 3. The process ofclarifyingand improving the color ofa'hydrocarbon petroleum whichconsists in .rapidly raising a commingled hydrocarbon oil .and aclarifying and decolorizing agent to the temperature of the desireddecolorizing reaction, maintaining such temperature to effect such reac-Y tion, immediately cooling the intermingled oil and agent to such atemperature as to prevent rapid oxidation, and separating the' a. entand adsorbed coloring mattei' from the o1 5. The process of clarifyingand improving the color of a hydrocarbon petroleum oil which consists inquickly raising such oil commingled with a finely divided clarifying anddecolorizing agent to the temperature of the desired decolorizingreaction, maintaining such temperature to effect said reaction,immediately cooling such oil and agent below the temperature of rapidoxidation, ,and separating the oil and agent with its adsorbed coloringmatter.

6. The ing the co or of a hydrocar on oil Which consists in rapidlycirculating throughl a heating chamber the oil intimately commingledwith a finely comminuted clarifying and decolorizing agent to cause thereaction of said oil and agent, immediately cooling the rocess of clarif'ing and improvsame to substantially prevent oxidation, and separatingthe oilfrom the agent and. its adsorbed matter.

7." The process of clarifying and decolorizing ahydrocarbon oil whichconsists in commingling the oil with a decolorizing agent, quicklyheating the same to approximately 300 F substantially vmaintaining thesame at substantially said temperature to eiect the reaction of said oiland agent, immediately cooling the same below the temperature of rapidoxidation; and separ-v ating the oil from the agent and its adsorbedmatter.

Signed at El Segundo, Calif., this 9th day MARVIN L. CHAPPELL. MERLE M.MOORE.

of February,

Witnesses:

G. M. HENDERSON, D. W. FALL.

